Field
Embodiments described herein relate to cleanliness control of process tool components, and more specifically to a particle collection apparatus and probe head for the collection of particles on process tool components.
Description of the Related Art
Substrate processing tool cleanliness “out of the box” is becoming an increasingly important issue during tool start-up. To consistently deliver clean tools, it is helpful to control cleanliness of substrate processing tools at the component and subsystem levels throughout the various stages of manufacturing and assembly. To control cleanliness, it is helpful to be able to measure cleanliness of the substrate processing tools at the desired particle sizes.
Substrate processing tools often involved complex geometries. The issue of measuring particle concentration on components of various materials and potentially complex geometry is different from the issue of measuring and characterizing particle levels on essentially planar substrates. Although metrology tools capable of detecting particles in the size range of 26 nm and below are available for substrates, and particles smaller than 26 nm can be imaged and measured on small samples that are capable of being placed in a scanning electron microscope (SEM), there are no commercial or high-volume manufacturing-worthy products available to measure particle concentration in the desired size range on the majority of the components that make up the substrate processing tools. Leading semiconductor industry roadmaps project critical defect size as half design rule critical dimensions (e.g., critical defect size of 10 nm for 20 nm node, and 5 nm critical defect size for 10 nm nodes). Current state of the art in surface particle metrology for substrate processing tool components (as opposed to substrates) is limited to particle sizes greater than or equal to 100 nm. In order to ensure the appropriate cleanliness of the substrate processing environment, all component surfaces in the substrate processing tool must be maintained at a certain level of cleanliness. This requirement extends throughout the entire tool manufacturing process.
Therefore, there is a need for devices and methods for improved particle detection on substrate processing tool components.